The film seemed to fall victim to a sinister curse. Star Gregory Peck and screenwriter David Seltzer took separate planes to the UK...yet BOTH planes were struck by lightning. While producer Harvey Bernhard was in Rome, lightning just missed him. Rottweilers hired for the film attacked their trainers. A hotel at which director Richard Donner was staying got bombed by the IRA; he was also struck by a car. After Peck canceled another flight, to Israel, the plane he would have chartered crashed...killing all on board. On day one of the shoot, several principal members of the crew survived a head-on car crash. The jinx appeared to persist well into post-production... when special effects artist John Richardson was injured and his girlfriend beheaded in an accident on the set of A Bridge Too Far (1977).

Harvey Stephens, as Damien, was largely chosen for this role from the way he attacked Richard Donner during auditions. Donner asked all the little boys to "come at him" as if they were attacking Katherine Thorn during the church wedding scene. Stephens screamed and clawed at Donner's face, and kicked him in the groin during his act. Donner whipped the kid off him, ordered the kid's blond hair dyed black and cast him as Damien.

According to at least one biography of Gregory Peck, he took this role at a huge cut in salary (a mere $250,000) but was also guaranteed 10% of the film's box office gross. When it went on to gross more than $60 million in the U.S. alone, The Omen (1976) became the highest-paid performance of Peck's career.

The biggest problem with shooting with Mrs. Baylock's ominous dog was that the animal was nothing like the creature he was supposed to be portraying. He wanted to lick and play with his co-stars rather than threaten them.

Jerry Goldsmith didn't want to attend the Academy Awards that year, since he had already lost multiple times before and didn't want to go through the ordeal of losing again. The Omen (1976) was Goldsmith's only Oscar.

To make the baboons attack the car in the Windsor Zoo park scene, an official from the zoo was in the back seat of the car with a baby baboon, but the baboons had no response at all. They then took the head of the baboons, and the baboons outside went crazy. Lee Remick's terror as the baboons attack the car was real.

Gregory Peck had essentially been retired for seven years when he quite unexpectedly agreed to make the film. By doing so, he effectively validated the production, and other members of the cast and crew soon came on board.

As part of its pre-release publicity campaign, and to point out the significance of "the three sixes" as The Sign of Satan, the movie was sneak-previewed nationwide in the USA on 6 June 1976. While audiences inside the theatres were being scared witless by the film, theatre employees were out front, busily putting up specially made posters declaring: "Today is the SIXTH day of the SIXTH month of Nineteen-Seventy-SIX!" Hokey though it was, the gimmick worked quite well, as many a theatre patron literally "freaked-out" upon seeing those posters as they left the previews.

Mrs. Baylock was originally written as a warm, effusive Irish nanny. For her audition, Billie Whitelaw significantly changed the dialogue to create the cold, slightly sinister character that subsequently appeared in the film.

One of Richard Donner's first requests to screenwriter David Seltzer was to remove all suggestions of the supernatural, such as cloven-hoofed demons and witches' covens. The golden rule was that nothing was allowed in the script that couldn't happen in real life. The idea was that there should be some degree of doubt over whether or not Thorn was deranged.

The taxi driver who takes Thorn around Italy was the son of a Mafioso in real life and was very keen to get into the movies. In one scene, he can quite clearly be seen sporting a large bandage on his thumb -- this was because Gregory Peck had accidentally slammed a car door on his hand, nearly taking off his finger.

David Seltzer has claimed that he only wrote the script because he needed the money. He has also asserted that he set it in London as he fancied a trip to England. He said of the film, "I did it strictly for the money. I was flat broke. I do find it horrifying how many people believe all this silliness".

Richard Donner and Harvey Bernhard asked Alan Ladd Jr., then the head of Twentieth Century Fox, for extra money during the film's post-production period to hire composer Jerry Goldsmith. They strongly felt that his music was right for the movie, after seeing him perform a live concert at the Hollywood Bowl earlier that year. Ladd was finally talked into giving Donner and Bernhard around $25,000 to hire Goldsmith, who would deliver his first and only Academy Award win for his score in 1977. Donner credits the success of the film to Goldsmith's score, which increased the tension and fear of the movie.

After finishing work on the film, special effects man John Richardson and his assistant were working on A Bridge Too Far (1977) in Holland. On their way back to their hotel one night their car was hit by a truck and the assistant killed instantly. John was knocked out and on coming to looked out of a window and saw a distant post which said 20 kilometres (to the town of) Ommen.

Because Harvey Stephens was so young, Richard Donner found that the best way to direct him was to provoke genuine reactions before the camera. For example, when Damien is angry at being taken to church, Donner got his peeved facial expression by shouting to Stephens off camera "What are you looking at you little bugger? I'll clobber you."

On the first day of shooting, one of the crew was in a head-on collision, and producer Harvey Bernhard's car was hit by another driver coming the wrong way out of a side street, which tore a front door off.

When Alan Ladd Jr. agreed to come on board as the film's producer, he insisted on Richard Donner joining the production as director. Donner -- up to then, mainly a TV director -- leapt at the chance to direct a major feature.

20th Century Fox originally passed on the film. Warner Brothers then optioned it for development, with Charles Bail directing. When they opted to make Exorcist II: The Heretic (1977) instead, The Omen was put in turnaround.

Gregory Peck's son had committed suicide before the production had even been cast. The producers were hesitant about sending him the script because a) the script deals with a man who's son has died and b) the man kills his son in the original ending. But Peck, amazingly, accepted the role in spite of this.

Billie Whitelaw was performing in a play at the West End when the film was being made. She rang up to ask if she could get out of making the film but as it was late on a Friday afternoon there was no one in the production office to receive her call. Whitelaw had no option but to show up for filming on the following Monday.

Gregory Peck and screen writer David Seltzer were in separate planes heading for London. An engine on Gregory's plane was knocked out by a bolt of lightning and eight hours later half way across the Atlantic Richard's plane was struck by lightning.

The movie was originally going to be called "The Birthmark", but a good chunk of the movie was filmed on location in Italian maternity wards, (for the beginning of the movie when Kathy gives birth in Rome). The crew would put up signs saying "Filming the Birthmark," and the women patients there would complain that they didn't want any mention of birthmarks in their maternity ward, for fear of bringing bad luck. The crew then started to change the signs to "Filming the Omen" just as a temporary measure. But then the new name seemed to stick--and they ran with it.

Richard Donner had read the script in one sitting and had heard that 20th Century Fox had already passed on the project. He repitched it to studio head Alan Ladd Jr. when the two were sitting down to dinner one night. Ladd was impressed with his enthusiasm and committed to the project.

Gregory Peck and Richard Donner had one argument during the production. Peck wanted to angrily smash things during the scene where Robert finds out his wife has died. Donner disagreed; he wanted to cut in on Thorn well after the discovery, not in the moment. According to Donner, he and Peck argued about the scene for an entire day before Peck told him, "You're wrong. I'm right. But you're the director, and therefore I have to do it your way." After the scene was shot, Peck reviewed the dailies and conceded that Donner had been right about how to film Thorn's reaction.

On the DVD at around 44 minutes just before the priest gets impaled he bangs on the door after banging the first door. Now if you look on the left of the second door it clearly says Muhammad and Allah in Arabic.

Richard Donner said he feared for his life during the filming of the movie, because of the "Omen curse". He literally feared the Devil or other demonic forces would strike him down during the production, but he soldiered on anyway. It should be noted that not only was Donner not killed during The Omen, but the film was very lucky for him. Its success opened the door for him to direct Superman 2 years later, which was a blockbuster success; and later the Lethal Weapon series, which was hugely successful; Goonies; and various other blockbusters. Overall, he has had a very prosperous and successful career, in spite of the Omen curse - and he is still alive.

This was originally going to be called "The Anti-Christ". When studio heads suggested something more subtle they appropriated the Nathaniel Hawthorne title: " The Birthmark". Eventually they made the title even more subtle; "The Omen".

Gregory Peck would star in another movie about the rise of a boy Antichrist figure in The Boys from Brazil (1978), with the same outcome. Although that boy would be a clone of Hitler, not the son of the devil.

The producers and Richard Donner were debating whether or not to keep the Mrs. Baylock character because while the rest of the movie was subtle and ambiguous enough to keep you guessing if it was really a demonic conspiracy or just a series of coincidences, Mrs. Baylock was so over the top evil, it was pretty clear she was straight from hell. This killed the ambiguity and suspense of the rest of the movie. But Donner loved Billie Whitlaw so much in this role he just couldn't bear to see her go.

This film, or at least elements of its plot, formed the basis of the satirical apocalyptic novel "Good Omens" by Terry Pratchett and Neil Gaiman. In fact, near the beginning of the book when a character is thinking of names for his newborn son, one of the nurses says, "Damien's very popular."

The zookeeper at the Zoosafari where the scene with the baboons, giraffes and other animals go crazy, was killed. The animals evidently went berserk during the baboons attack scene, and when he tried to intervene he was unfortunately killed by the zoo animals. This is one of the incidents that Richard Donner and other people associated with the production point to as evidence that there's an Omen curse. Unfortunately, there is no proof that the zookeeper was killed during the baboon scene by baboons or any other animal.

The plot of this movie owes more than a small debt to Rosemary's Baby (1968) and The Exorcist (1973); both demon child flicks that came right before it, as well as Night of the Demon; which involves a demonic cult and a series of grisly "accidents" which kill off enemies of the cult. Whereas the other two focus on the mother in a family, this one focuses on the father. Whereas they take place in the U. S., this takes place in Europe. The Omen and The Exorcist both started long running franchises. They both had many sequels and remakes and spin-offs which made lots of money. But Rosemary's Baby did not. It had one TV movie sequel called Look What's Happened to Rosemary's Baby (1976) which featured Ruth Gordon reprising her Academy Award winning performance from the original film, but was poorly received by critics and fans alike, and then it ended. Furthermore, Mia Farrow appeared in The Omen (2006).

The PR team associated with the movie seized upon a myriad of coincidences and accidents associated with the production; playing up (or embellishing) the idea of an Omen curse to try to get the audiences appropriately spooked and by default interested in the film. The studios did the same thing with Poltergeist (1982) and The Exorcist (1973), which all allegedly have curses associated with their productions.

Rosemary's Baby (1968) follows a similar plot, about a satanic conspiracy involving the rise to power of the devil's son, and the series of accidents and deaths that are inflicted upon the opponents to this conspiracy. But whereas that film is very subtle, this is more explicit. For example, when Hutch dies after giving key information about the Castavets and the coven to Rosemary, it's easy to miss that his death was a result of the coven's intervention; it's very subtle. But when Father Brennan warns Robert about Damien and immediately thereafter is impaled by a metal rod which is struck by lightning, it's impossible to miss the Devil's handiwork.

It was Richard Donner's intention to film and edit the scene where Jennings is decapitated in such a way that the audience, having closed their eyes at the beginning of the scene, would open them only to see the head still floating in the air.

Richard Donner made a TV movie prior to this with Jack Palance called Bronk (1975). When Palance heard that Donner's next project was to be made in England, he urged his director to seek out his daughter, since she was a great actress. Donner did precisely that, and subsequently cast Holly Palance as Damien's ill-fated first nanny.

In the closing scene, Richard Donner used reverse psychology on young Harvey Stephens telling him, "Don't you dare laugh. If you laugh, I won't be your friend." Naturally, Stephens wanted to laugh, and he instead smiled directly into the camera.

The original ending had all three members of the Thorn family killed at the conclusion. Studio head Alan Ladd Jr. felt that this was a mistake. After all, the devil is impossible to kill, he reasoned. He subsequently gave Richard Donner the additional funds necessary to shoot a more open ending to the film.

Lee Remick refused to shoot the tricycle ambush scene as originally conceived: She was originally going to fall from the balcony, with stunt people and staff underneath to brace her fall. Though Richard Donner begged her, on the day before the stunt, she adamantly refused, letting her own fears get the best of her, that coupled with Omen's Curse disasters seeming to compound everything. Donner reconfigured the shot so that she wouldn't actually fall, she would just be slid standing up from one piece of the set to another, but it was shot in a way that made her look like she was falling.

In the original ending Robert kills Damien at the church, and good triumphs. However the MPAA said this scene was too shocking, which ironically brought about the ending where Robert gets shot and the Antichrist triumphs.

While critics tore into The Exorcist (1973) for being too gratuitously gory, this film was almost universally praised for its discreet use of gore. In fact, although there are many grisly deaths, there is still almost no bloodshed. That didn't stop it from nearly getting an X rating due to its gory decapitation scene.

The wine spilling in the back of the truck while David Warner's character is decapitated is supposed to suggest blood. The filmmakers could not actually show bloodshed at this point without obtaining an X rating.

The end of this movie borrows from The Bad Seed (1956), the beginning of the evil child horror movie subgenre. Christine, the protagonist of the story, has a young daughter named Rhoda, the eponymous bad seed, a serial killer. At the climax, Christine gives Rhoda an overdose of sleeping pills, and then kills herself, hoping to put an end to her daughter's genetic predatory instincts. Unfortunately Rhoda survives her mother's poisoning attempt, and at the end she taunts the audience by smiling and leering at them, indicating that she will kill again. Damien too survives his father's attempt to kill him, and smugly smiles at the audience, indicating that his reign of terror is also not over.

Damien doesn't actually kill anyone in this movie. Rather a series of accidents occur which kill off his enemies, and it's implied that the Devil is behind these accidents (not the Devil's son). Comparatively speaking, Regan from The Exorcist (1973), who brutally murders Burke Dennings with her bare hands, is much more dangerous.